MOSCOW (AP) -- With a blinding flash and a booming shock wave, a meteor blazed across the sky over Russia's Ural Mountains region Friday and exploded with the force of an atomic bomb, injuring more than 1,000 people as it blasted out windows and spread panic in a city of 1 million. While NASA estimated the meteor was only about the size of a bus and weighed about 7,000 tons, the fireball it produced was dramatic. Video shot by startled residents of the city of Chelyabinsk showed its streaming contrails arcing toward the horizon just after sunrise, looking like something from a world-ending science-fiction movie. It came hours before a 150-foot asteroid passed within about 17,000 miles (28,000 kilometers) of Earth. The European Space Agency said its experts had determined there was no connection between the asteroid and the Russian meteor - just cosmic coincidence. The meteor over Russia entered the Earth's atmosphere about 9:20 a.m. local time (10:20 p.m. EST Thursday) at a hypersonic speed of at least 33,000 mph (54,000 kph) and shattered into pieces about 30-50 kilometers (18-32 miles) high, the Russian Academy of Sciences said. NASA estimated its speed at about 40,000 mph and the energy released in the hundreds of kilotons. "There was panic. People had no idea what was happening," said Sergey Hametov of Chelyabinsk, about 1,500 kilometers (930 miles) east of Moscow. "We saw a big burst of light, then went outside to see what it was and we heard a really loud, thundering sound," he told The Associated Press by telephone. The shock wave blew in an estimated 100,000 square meters (more than 1 million square feet) of glass, according to city officials, who said 3,000 buildings in Chelyabinsk were damaged. At a zinc factory, part of the roof collapsed. The Interior Ministry said about 1,100 people sought medical care after the shock wave and 48 were hospitalized. Most of the injuries were caused by flying glass, officials said. Emergency Situations Ministry spokesman Vladimir Purgin said many of the injured were cut as they flocked to windows to see what caused the intense flash of light, which momentarily was brighter than the sun. There was no immediate word on any deaths or anyone struck by space fragments. President Vladimir Putin summoned the nation's emergencies minister and ordered immediate repairs. "We need to think how to help the people and do it immediately," he said. Some meteorite fragments fell in a reservoir outside the town of Chebarkul, the regional Interior Ministry office said. The crash left an eight-meter (26-foot) crater in the ice. Lessons had just started at Chelyabinsk schools when the meteor exploded, and officials said 258 children were among those injured. Amateur video showed a teacher speaking to her class as a powerful shock wave hit the room. Yekaterina Melikhova, a high school student whose nose was bloody and whose upper lip was covered with a bandage, said she was in her geography class when a bright light flashed outside. "After the flash, nothing happened for about three minutes. Then we rushed outdoors. ... The door was made of glass, a shock wave made it hit us," she said. Russian television ran video of athletes at a city sports arena who were showered by shards of glass from huge windows. Some of them were still bleeding.